A two dimensional collimator assembly and method of manufacturing thereof is disclosed. The collimator assembly includes a wall structure constructed to form a two dimensional array of channels to collimate x-rays. The wall structure further includes a first portion positioned proximate the object to be scanned and configured to absorb scattered x-rays and a second portion formed integrally with the first portion and extending out from the first portion away from the object to be scanned. The first portion of the wall structure has a height greater than a height of the second portion of the wall structure. The second portion of the wall structure includes a reflective material coated thereon in each of the channels forming the two dimensional array of channels.